How make unity guess a different number?

The program is a simple number guessing game however when i randomize the guesses unity tends to pick the same number multiple times is there a way to have it know what numbers it already picked? an also is there a way to make it automatically go to the lose scene if it can’t pick another number? any help is appreciated :slight_smile:

void NextGuess()
 guess = (max + min) / 2;
 //guess = Random.Range (min,max);//Randomizes Guesses 
 //print (guess); 
 text.text = guess.ToString ();
 maxGuessesAllowed = maxGuessesAllowed - 1; 
 if (maxGuessesAllowed <= 0) 
   Application.LoadLevel ("Win"); 

Make it pick a value out of list of possible answers, every time you pick one you remove it.